Caster



March 16 1926. 1,576,922

E. T. MALLOY CASTER Filed March 18, 1922 atten/w11 Patented lvfiar. iti, IQE.

UNt'llitE' STATES EDWARD r. MALLOY, or HAMILTON, orrio.-

CASTER.

Application 'filled March 18, 1922.

To all 207mm t may concern.'

Be it known that l, Enwniin T. Matrici', a citizen of the `United States, residing at Hamilton, in the county of' Butler and' State of Ohio, have invented certain new and useful Improvements in Casters, of which the following is a specification.

My invention relates to improvements in casters. Onel of its objects is to provide a caster having an improvedstep or thrust bearing.l Another object is to provide an improved'hall cage, another object is `to provide improved bearing plates orl faces for the balls to travel on. Another object is to provide improved means to prevent the roller axle from rotating relative to the caster frame. Another object is to provide an improved caster assembly. My invention also comprises certain details of form, combination and arrangement all of which will be fully set forth in the description of the accompanying drawings in which:

Fig. 1, is a side elevation of a caster einbodying my improvements.

25 Fig. 2, is a vertical section throughl the same on line 2--2 ofFig. 1.

Fig. 3, is a plan viewiof the caster shown in Fig. 1.

Fig. 4, is a perspective view of the caster 30 plate detached.

Fig. 5 is a perspective view of one of ball plates. I

Fig. 6 is a perspective view of the ball cage or spacer detached. j

Fig. 7, is a perspective view of the caster wheel axle detached.

The accompanying drawings illustrate the preferred embodiment of my invention in which 15 represents the caster plate pro-V vided with screw holes y16, or other means by which said caster plate may berigidly attached to an object to be supported upon casters. The caster plate is preferably provided with a tubular projection 17 through which a king-bolt cap screw or rivet 18 is inserted and secured in place relative thereto.

A caster hou-sing or frame 19 is provided with two downwardly projecting arms 20 and 21 which serve as supports for opposite ends of the caster wheel axle 22. rllhe caster wheel 24 is journaled upon the caster wheel axle 22, which axle is designed not to rotate relative to the arms 2O and 21 of the caster iframe. The upper face 25 of the caster frame is lane, or if preferred may be pro-1 vided witi a short tubular upward projeccra Serial No. 544,910.

tion `26. Mounted loosely upon the upper face 25 of the caster frame and retained centrally thereon byV theprojection 26, or in the absence of projection by the projection 17 is a relatively thin hardened plate 27 preferably a hardened sheet iron or steel plate or washer as shown in 5. Mounted loosely upon .the plate 27 is a ball cage er ball spacer 28` carrying a plurality of steel balls 29. A hardened ironor steel plate or washer 30 is mounted loosely upon and above the balls 29 and spacer 28 and the caster plate 15 is inountedloosely upon the steel plate 80. The tubular projection 17 of thel caster plate 15 projects downwardlythrough the plate 30, spacer 28, plate 27, and through a vertical recess 31 in the caster frame 19 so as to retain the plateI 30 in a central posi.ltion withreferenceto the caster plate 15 75 upon the annular baseV section 32 of the projection 17 and so as to retain the ball cage 28 in asubstantially centralv position with reference to the caster fra-me lathrough engagement with the annular section 33 80 of -the tubular projection 17; A ball raceway 311 isformed in the caster frame' 19 and provided with aseries of balls 35 which are retained in place by a sheet metal washer or plate 3G held in place rigidly upon the 85 outer end of the tubular projection 17 by means of therivet 18,oi1 if'd'esired by means of a` king-bolt or cap screw 18" in'pla'ce of said rivet. Y

itis designed to .employ unfinished cast- 9 ings for the plate 15 and frame 19, except that said castings are bored to receive the axle 22 and rivet 18. VThe hardened steel plates 27 and 30' are relatively thin but present smooth hard plane faces to the balls and `resist the formation of groove-s or dents in thefaces thereof under normal strains lThe plates 27 and 30 are placed against the unfinished faces of the plate 15 and frame-19 in order to secure harder and smoother faces than would be afforded by the unfinished castings,l and also to 'afford a more extensive wearing face opposite the balls This iii-- creased wearing face is attained through i the plates 27 and 30 being free to move relalo tive to the plate 15 and frame 19 so as to successively but slowly change their relative positions so as to successively present different fractions of the faces of the plates 27 and 30 at the points where the balls 29 bear most heavily upon the faces of said plates 27 and 30,- and the. prevent the formaL tion of local grooves or depressions in the plates 27 and 30, and insure a much more extended wearing surface and a. more uniform strain and Wear thereon. The balls assist the balls 29 in supporting the plate 15 and frame 19 in the desired relative position and to resist lateral strain tending to displace them due to the caster wheel axle being located at one side of the axis oit the king-rivet 18. The balls 29 and 35 coact to insure a .practically frictionless movement of the caster trame 19 relative to the plate 15 irrespective of heavy weights supported upon the plates 15 and the strain laterally due to the caster wheel axle being ott-set relative to the king-rivet 18. The normal tendency o1c the olf-set position ol: the caster wheel axle relative to the king-rivet is to place an excessive strain Vupon a. portion only of the balls and a fraction of the bearing surfaces engaged by the balls, and hence to make local depressions in the bearing surfaces engaged by the balls.

The use of the plates 27 and SOtends to greatly increase the useful life of the casters, since in addition to the increasedl original life of the casters the plates 27 and 30 are readily renewable if worn or fractured, and even where fractured and renewal is neg lected, the fragments of the fractured plate 27 or 30 drop out and a new unlinished tace of the plate 15 or frame 19 becomes a bearing surface for the balls 29 until repairs` are made.

In order to support the caster wheel axle 22 in substantially non-rotatable relation to the arms 20 and 21 of the easter trame so that the caster wheel will rotate upon the axle 22 in place of the axle 22 rotating relative to the frame 19, I provide one or more ribsor projections 40 on the outside of the arms 2O and 21 having a face 41 to engage a face 42 on the head 43 of the caster wheel axle to prevent said axle from turning relative to the frame 19. After the axle 22 and wheel 24 have been assembled, the end 44 of the axle opposite its head may be headed or riveted over as shown in Fig. 2, to prevent detachment of the axle 22, or the end 44 of the axle may be provided with a perforation 45 to receive a cotter pin to detachably retain the axle 22 in place relative to the frame 19. y

The ball spacer 28 comprises a main disk or annular plate having a series ol tapered perorations 46 each with a rim 47 raised from the plate 28 at the wider end oi the perforations 46. The perforations are of sutlicient diameter to receive thc balls 29 at their wider ends but not to pass the balls through their narrower ends. rIhe ball spacers 28 are designed to be used as unnished castings, and when held with the rims 47 upward, said ball spacers are adapted to be inserted beneath the surface of a quantity ol" balls in a container so as to emerge with each ofthe perforations 4G charged with ball, while the surplus balls roll off the spacer back into the container, thereby electing a considerable saving in time over a form of spacer requiring a linishing` operation or to have each ball inserted therein one at a time. Tvll/'hen assembled the bals 29 are retained in operative relation even though a portion of the plate 15 should become broken and detached.

My improved caster is low in labor and material'cost, and adapted to efficiently serve its purpose for long periods of time without attention. It is readily restored to useful condition when required.

he apparatus herein shown and dessi-'bed is capable of considerable modilication without departing `from the spirit of my invention. Y

What I claim is:

Arcaster comprising a caster plate, having a downwardly directed tubular projection, a caster `frame provided with a easter wheel, a hing-bolt member passing through said tubular projection and interposed between the caster plate and caster frame, a separable annular ball spacer interposed between said caster plate and caster frame and held concentrically in position by the downwardly directed tubular projection of said caster plate, said ball spacer being provided with a plurality of conical ball recesses ot less diameter at their narrow ends than the diameter of the spacer balls and with raised rims at the wider ends of said ball recesses, end thrust balls located in said spacer ball recesses, a ball radial thrust bearing encircling said king bolt men'iber at its lower end and radial thrust balls located in said radial thrust bearing to take both the end thrust and radial thrust ot said caster 'frame upon said caster plate. l

In testimony whereof I have allixed my signature.

EITWARD T. lvlLLO'Y. 

